#ifndef LEX_H
#define LEX_H

#include "typeutils.h"


typedef struct ExpansionRegion ExpansionRegion;


typedef enum {
    UN_Q,
    SINGLE_Q,
    DOUBLE_Q,
} QuotationMode;

typedef enum {
    LITERAL,
    REGION_EXP,
    VAR_EXP,    // TODO: Later include other exps
} ChunkKind;

typedef struct {
    ChunkKind kind;
    QuotationMode qmode;
    union {
        char* literal_str;
        ExpansionRegion* reg_ptr;
        char* varname;
    } as;
} Chunk;


DECLARE_VEC(Chunk, ChunkVec)

typedef enum {
    TOK_WORD,
    TOK_SPECIAL,
} TokenKind;

typedef enum {
    PIPE,
    WRITE_REDIR_TRUNC,
    WRITE_REDIR_APPEND,
    READ_REDIR,
    L_PROC_SUB_IN,
    L_PROC_SUB_OUT,
    PAREN,
    EOL,
} SpecialToken;

typedef struct {
    TokenKind kind;

    union {
        ChunkVec word;
        SpecialToken spec; 
    } as;
} Token;
    

DECLARE_VEC(Token, TokenVec)

DECLARE_MAYBE(SpecialToken)  

typedef enum {
    CMD_SUB,
    ARITHM,
} RegionMode;

struct ExpansionRegion {
    RegionMode mode;
    TokenVec tokens; 
};

DECLARE_MAYBE(Chunk);

DECLARE_VEC(ExpansionRegion, ExpansionRegionVec)


typedef struct {
    TokenVec top_tokens;
    ExpansionRegionVec reg_arena;
} LexResult;


LexResult lex(char* input);

#endif